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1.
Mayo Clin Proc ; 97(8): 1586, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35933146

Assuntos
Humanos , Indonésia , Ilhas
2.
Proc Biol Sci ; 289(1980): 20221105, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35946156

RESUMO

The presence of migratory birds on islands results in seasonal variation in species richness. These patterns and their geographical correlates within the context of island biogeography theory have not been examined. We used 21 years of bird observations on 690 islands from eBird to determine how seasonal species richness estimates vary as a function of island area, isolation and latitude. Species richness was highest on islands within the northern mid-latitudes during migration and on islands within tropical latitudes during the non-breeding season. Area defined positive, nonlinear relationships with species richness across seasons, with the steepest slopes occurring with islands greater than 1100 km2. Distance to mainland defined negative, nonlinear relationships with species richness across seasons, with the strongest slopes occurring with islands located greater than 150 km from the mainland. Species-area relationships were weakest for the most remote islands and strongest for islands at intermediate distances to the mainland. Intermediate proximity to other islands was a poor predictor of species richness. Our findings emphasize the presence of seasonally dynamic geographical relationships, the enhanced role of evolutionary processes on larger islands, the unique ecology of the world's most remote islands, and the importance of islands as stopover sites and wintering grounds for migratory bird species.


Assuntos
Biodiversidade , Aves , Animais , Geografia , Ilhas , Estações do Ano
3.
J Helminthol ; 96: e51, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35856271

RESUMO

The influence of climate on parasite distribution has been demonstrated in different regions worldwide. Despite its small size, Gran Canaria (Canary Islands, Spain) constitutes a 'biodiversity laboratory' due to the huge climatic differences between municipalities. Feral cats may represent a threat to biodiversity due to their predatory behaviour. In addition, they may be a source of pathogens zoonotic to humans. To study the climatic/seasonal influence and prevalence of feral cat parasites throughout the island, a total of 290 stool samples from 29 feral cat colonies were analysed following standard concentration protocols (sodium chloride, formol-ether and zinc sulphate). In total, 13 feline parasitic taxa were found, with the most common species being Ancylostoma spp., which, together with Toxocara spp., Toxoplasma gondii and Giardia spp., are considered a concern for human health. Nematodes were the most common parasites in all areas. Nematodes and protozoans were significantly more prevalent in temperate mild (75.0% and 30.0%) than in dry desert areas (29.3% and 18.7%). In contrast, cestodes were significantly more prevalent in dry desert than in temperate mild areas (26.0% and 13.3%). Only protozoans exhibited statistically significant seasonal patterns, mostly in the wet season. Data reported in this study endorse the usage of small and diverse islands such as Gran Canaria to study the climatic influence on parasitic communities in wild/feral animals. Cat colonies require better management to reduce their threat to endemic wildlife, domestic animals and public health, being invasive species that harbour zoonotic parasites.


Assuntos
Doenças do Gato , Parasitos , Animais , Animais Selvagens , Doenças do Gato/epidemiologia , Gatos , Ecossistema , Humanos , Ilhas , Zoonoses/epidemiologia , Zoonoses/parasitologia
4.
Environ Monit Assess ; 194(7): 479, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35666327

RESUMO

The rapid coastal development in the Andaman Islands has resulted in littoral habitat degradation. Understanding the performances of marine biotic indices and the interpretation and translation of those results into coastal health assessment could become an integral tool in future monitoring and management policies. In this line of efforts, the ecological quality status of three sandy beaches, two urban and one nonurban, was evaluated by using three marine biotic indices. The faunal community belonged to moderately well-sorted fine sand biocenosis. The relatively high species richness (15.9 ± 0.80 taxa sample-1) and moderate abundance (563 ± 38.8 ind.m-2) were features of the benthic fauna. The urban beaches (Aberdeen Bay and Carbyn's Cove) corresponded to tolerant benthic communities. Malacoceros indicus, Grandidierella megnae and Scolelepis squamata (tolerant species), and Ampelisca diadema (indifferent species) were the major constituents of urban beaches, while Scoloplos capensis, Urothoe grimaldii, and Urothoe platydactyla (sensitive species) were important at the nonurban beach (Wandoor). The high-good quality status prevailed across the spatial and temporal scales except for Carbyn's cove beach, where good-poor status was noticed. The M-AMBI appeared to be the most robust measure in distinguishing the impact between the urban and nonurban beaches. The constrained ordinations revealed a gradient of disturbance across the beaches. The distinct patterns of sample segregation were the result of the ecological response. This attempt should be considered a comprehensive measure of quality assessment of beaches under human pressure and draw a parallel line of evidence to global studies on sandy beaches.


Assuntos
Poliquetos , Areia , Animais , Praias , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Ilhas
5.
Int J Mol Sci ; 23(12)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35742848

RESUMO

Heat shock protein 20 (Hsp20) is a major family of heat shock proteins that mainly function as molecular chaperones and are markedly accumulated in cells when organisms are subjected to environmental stress, particularly heat. Canavalia rosea is an extremophile halophyte with good adaptability to environmental high temperature and is widely distributed in coastal areas or islands in tropical and subtropical regions. In this study, we identified a total of 41 CrHsp20 genes in the C. rosea genome. The gene structures, phylogenetic relationships, chromosome locations, and conserved motifs of each CrHsp20 or encoding protein were analyzed. The promoters of CrHsp20s contained a series of predicted cis-acting elements, which indicates that the expression of different CrHsp20 members is regulated precisely. The expression patterns of the CrHsp20 family were analyzed by RNA sequencing both at the tissue-specific level and under different abiotic stresses, and were further validated by quantitative reverse transcription PCR. The integrated expression profiles of the CrHsp20s indicated that most CrHsp20 genes were greatly upregulated (up to dozens to thousands of times) after 2 h of heat stress. However, some of the heat-upregulated CrHsp20 genes showed completely different expression patterns in response to salt, alkaline, or high osmotic stresses, which indicates their potential specific function in mediating the response of C. rosea to abiotic stresses. In addition, some of CrHsp20s were cloned and functionally characterized for their roles in abiotic stress tolerance in yeast. Taken together, these findings provide a foundation for functionally characterizing Hsp20s to unravel their possible roles in the adaptation of this species to tropical coral reefs. Our results also contribute to the understanding of the complexity of the response of CrHsp20 genes to other abiotic stresses and may help in future studies evaluating the functional characteristics of CrHsp20s for crop genetic improvement.


Assuntos
Antozoários , Proteínas de Choque Térmico , Animais , Antozoários/genética , Antozoários/metabolismo , Canavalia/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Ilhas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
6.
Nature ; 606(7913): 329-334, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35650439

RESUMO

The sexual strain of the planarian Schmidtea mediterranea, indigenous to Tunisia and several Mediterranean islands, is a hermaphrodite1,2. Here we isolate individual chromosomes and use sequencing, Hi-C3,4 and linkage mapping to assemble a chromosome-scale genome reference. The linkage map reveals an extremely low rate of recombination on chromosome 1. We confirm suppression of recombination on chromosome 1 by genotyping individual sperm cells and oocytes. We show that previously identified genomic regions that maintain heterozygosity even after prolonged inbreeding make up essentially all of chromosome 1. Genome sequencing of individuals isolated in the wild indicates that this phenomenon has evolved specifically in populations from Sardinia and Corsica. We find that most known master regulators5-13 of the reproductive system are located on chromosome 1. We used RNA interference14,15 to knock down a gene with haplotype-biased expression, which led to the formation of a more pronounced female mating organ. On the basis of these observations, we propose that chromosome 1 is a sex-primed autosome primed for evolution into a sex chromosome.


Assuntos
Evolução Molecular , Ilhas , Planárias , Reprodução , Cromossomos Sexuais , Animais , Mapeamento Cromossômico , Feminino , Genoma/genética , Endogamia , Masculino , Planárias/genética , Cromossomos Sexuais/genética
7.
An Acad Bras Cienc ; 94(suppl 1): e20210683, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544839

RESUMO

Monitoring and inventorying proglacial lakes in the Maritime Antarctica region is essential for understanding the effects of climate change on these environments. This study uses Landsat images to create a map of lakes in ice-free areas of the South Shetlands Islands (SSI) for 1986/89, 2000/03 and 2020, and verification of patterns of change in lake areas and numbers. Normalized water difference index (NDWI) products, image segmentation, field records, and cartographic products from other studies were used to validate the results. Results show a 60% increase in the number of lakes from 1986/89 to 2000/03; and a 55% increase from 2000/03 to 2020. There was a 52% increase in lake areas from 1986/89 to 2000/03; a 79% increase from 2000/03 to 2020; and a 173% increase from 1986 to 2020. From 1986 to 2020, the most significant changes were a decrease in the average elevation and distance from glaciers and an increase in distance from the sea. In 2020, SSI lakes were predominantly coastal and ice-marginal, with an E and S orientations, flat surfaces, and a low declivity.


Assuntos
Camada de Gelo , Lagos , Regiões Antárticas , Mudança Climática , Monitoramento Ambiental , Ilhas
8.
Proc Natl Acad Sci U S A ; 119(22): e2112737119, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35617436

RESUMO

Tropical alpine floras are renowned for high endemism, spectacular giant rosette plants testifying to convergent adaptation to harsh climates with nightly frosts, and recruitment dominated by long-distance dispersal from remote areas. In contrast to the larger, more recent (late Miocene onward) and contiguous expanses of tropical alpine habitat in South America, the tropical alpine flora in Africa is extremely fragmented across small patches on distant mountains of variable age (Oligocene onward). How this has affected the colonization and diversification history of the highly endemic but species-poor afroalpine flora is not well known. Here we infer phylogenetic relationships of ∼20% of its species using novel genome skimming data and published matrices and infer a timeframe for species origins in the afroalpine region using fossil-calibrated molecular clocks. Although some of the mountains are old, and although stem node ages may substantially predate colonization, most lineages appear to have colonized the afroalpine during the last 5 or 10 My. The accumulation of species increased exponentially toward the present. Taken together with recent reports of extremely low intrapopulation genetic diversity and recent intermountain population divergence, this points to a young, unsaturated, and dynamic island scenario. Habitat disturbance caused by the Pleistocene climate oscillations likely induced cycles of colonization, speciation, extinction, and recolonization. This study contributes to our understanding of differences in the histories of recruitment on different tropical sky islands and on oceanic islands, providing insight into the general processes shaping their remarkable floras.


Assuntos
Mudança Climática , Plantas , África Oriental , Ecossistema , Variação Genética , Humanos , Ilhas , Plantas/anatomia & histologia , Plantas/genética , População
9.
Mar Pollut Bull ; 180: 113751, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35597002

RESUMO

Molecular genetic studies of stools were performed to assess the spread of some clinically relevant antimicrobial resistance determinants (ARD) in a gentoo penguin (Pygoscelis papua) and an Antarctic fur seal (Arctocephalus gazella) on Livingston Island. Glycopeptide resistance genes (vanA/vanD and vanB) were detected in both fecal samples, while the penguin's one was also mecA-positive and blaNDM-positive. Because of the remoteness and the isolation of the sampling locations, the carriage of vancomycin-resistant Enterococcus spp., methicillin-resistant Staphylococcus aureus, and NDM-producing Enterobacterales or other gram-negative bacilli suggested an ocean pollution with antibiotic resistant bacteria (ARB). Additionally, due to the type of ARD we detected, our results are alarming, and they cannot be explained only with agricultural and/or aquacultural pollution. Even though the current study is a preliminary one, it also demonstrates the potential of the field genetics analyses carried out with minimal equipment as a reliable monitoring tool for pollution with ARB.


Assuntos
Otárias , Staphylococcus aureus Resistente à Meticilina , Spheniscidae , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Animais , Regiões Antárticas , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Ilhas , Biologia Molecular
10.
Syst Parasitol ; 99(4): 491-523, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35553301

RESUMO

In 2014-2015 and 2019-2021, teleost fishes off Galindez Island (Antarctic Peninsula) were examined for trematodes. Combined morphological and molecular analyses revealed the presence of eight trematode species of four families (Hemiuridae, Lecithasteridae, Opecoelidae, Lepidapedidae) from five fish species. Only adult trematodes were found and all of them are Antarctic endemics with their congeners occurring on other continents. The hemiuroids, Elytrophalloides oatesi (Leiper & Atkinson, 1914), Genolinea bowersi (Leiper & Atkinson, 1914), and Lecithaster macrocotyle Szidat & Graefe, 1967 belong to the most common Antarctic species and together with Lepidapedon garrardi (Leiper & Atkinson, 1914) and Neolebouria georgiensis Gibson, 1976 they were recorded as the least host-specific parasites. The originally sub-Antarctic Neolepidapedon macquariensis Zdzitowiecki, 1993 is a new record for the Antarctic Peninsula and Parachaenichthys charcoti (Vaillant), is a new host record. Neolebouria terranovaensis Zdzitowiecki, Pisano & Vacchi, 1993 is considered a synonym of N. georgiensis because of identical morphology and dimensions. The currently known phylogenetic relationships within the studied families are supported, including the polyphyly of Macvicaria Gibson & Bray, 1982 with the future need to accommodate its Antarctic species in a new genus. The validity of M. georgiana (Kovaleva & Gaevskaja, 1974) and M. magellanica Laskowski, Jezewski & Zdzitowiecki, 2013 needs to be confirmed by further analyses. Genetic sequence data are still scarce from Antarctica, and more studies applying integrative taxonomic approaches and large-scale parasitological examinations of benthic invertebrates are needed to match sequences of larval stages to those of well-characterised adults and to elucidate trematode life-cycles.


Assuntos
Trematódeos , Animais , Regiões Antárticas , Peixes/parasitologia , Ilhas , Filogenia , Especificidade da Espécie
11.
PLoS One ; 17(5): e0263866, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35584085

RESUMO

BACKGROUND: It is critical to capture data and modeling from the COVID-19 pandemic to understand as much as possible and prepare for future epidemics and possible pandemics. The Hawaiian Islands provide a unique opportunity to study heterogeneity and demographics in a controlled environment due to the geographically closed borders and mostly uniform pandemic-induced governmental controls and restrictions. OBJECTIVE: The goal of the paper is to quantify the differences and similarities in the spread of COVID-19 among different Hawaiian islands as well as several other archipelago and islands, which could potentially help us better understand the effect of differences in social behavior and various mitigation measures. The approach should be robust with respect to the unavoidable differences in time, as the arrival of the virus and promptness of mitigation measures may vary significantly among the chosen locations. At the same time, the comparison should be able to capture differences in the overall pandemic experience. METHODS: We examine available data on the daily cases, positivity rates, mobility, and employ a compartmentalized model fitted to the daily cases to develop appropriate comparison approaches. In particular, we focus on merge trees for the daily cases, normalized positivity rates, and baseline transmission rates of the models. RESULTS: We observe noticeable differences among different Hawaiian counties and interesting similarities between some Hawaiian counties and other geographic locations. The results suggest that mitigation measures should be more localized, that is, targeting the county level rather than the state level if the counties are reasonably insulated from one another. We also notice that the spread of the disease is very sensitive to unexpected events and certain changes in mitigation measures. CONCLUSIONS: Despite being a part of the same archipelago and having similar protocols for mitigation measures, different Hawaiian counties exhibit quantifiably different dynamics of the spread of the disease. One potential explanation is that not sufficiently targeted mitigation measures are incapable of handling unexpected, localized outbreak events. At a larger-scale view of the general spread of the disease on the Hawaiian island counties, we find very interesting similarities between individual Hawaiian islands and other archipelago and islands.


Assuntos
COVID-19 , COVID-19/epidemiologia , Hawaii/epidemiologia , Humanos , Ilhas , Pandemias , SARS-CoV-2
12.
Biol Lett ; 18(4): 20220030, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35440235

RESUMO

Animals on islands typically depart from their mainland relatives in assorted aspects of their biology. Because they seem to occur in concert, and to some extent evolve convergently in disparate taxa, these changes are referred to as the 'island syndrome'. While morphological, physiological and life-history components of the island syndrome have received considerable attention, much less is known about how insularity affects behaviour. In this paper, we argue why changes in personality traits and cognitive abilities can be expected to form part of the island syndrome. We provide an overview of studies that have compared personality traits and cognitive abilities between island and mainland populations, or among islands. Overall, the pickings are remarkably slim. There is evidence that animals on islands tend to be bolder than on the mainland, but effects on other personality traits go either way. The evidence for effects of insularity on cognitive abilities or style is highly circumstantial and very mixed. Finally, we consider the ecological drivers that may induce such changes, and the mechanisms through which they might occur. We conclude that our knowledge of the behavioural and cognitive responses to island environments remains limited, and we encourage behavioural biologists to make more use of these 'natural laboratories for evolution'.


Assuntos
Evolução Biológica , Animais , Ilhas
13.
PLoS One ; 17(4): e0266424, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35413068

RESUMO

Passive acoustic monitoring (PAM) has proven a powerful tool for the study of marine mammals, allowing for documentation of biologically relevant factors such as movement patterns or animal behaviors while remaining largely non-invasive and cost effective. From 2008-2019, a set of PAM recordings covering the frequency band of most toothed whale (odontocete) echolocation clicks were collected at sites off the islands of Hawai'i, Kaua'i, and Pearl and Hermes Reef. However, due to the size of this dataset and the complexity of species-level acoustic classification, multi-year, multi-species analyses had not yet been completed. This study shows how a machine learning toolkit can effectively mitigate this problem by detecting and classifying echolocation clicks using a combination of unsupervised clustering methods and human-mediated analyses. Using these methods, it was possible to distill ten unique echolocation click 'types' attributable to regional odontocetes at the genus or species level. In one case, auxiliary sightings and recordings were used to attribute a new click type to the rough-toothed dolphin, Steno bredanensis. Types defined by clustering were then used as input classes in a neural-network based classifier, which was trained, tested, and evaluated on 5-minute binned data segments. Network precision was variable, with lower precision occurring most notably for false killer whales, Pseudorca crassidens, across all sites (35-76%). However, accuracy and recall were high (>96% and >75%, respectively) in all cases except for one type of short-finned pilot whale, Globicephala macrorhynchus, call class at Kaua'i and Pearl and Hermes Reef (recall >66%). These results emphasize the utility of machine learning in analysis of large PAM datasets. The classifier and timeseries developed here will facilitate further analyses of spatiotemporal patterns of included toothed whales. Broader application of these methods may improve the efficiency of global multi-species PAM data processing for echolocation clicks, which is needed as these datasets continue to grow.


Assuntos
Golfinhos , Ecolocação , Baleia Comum , Acústica , Animais , Cetáceos , Hawaii , Ilhas , Aprendizado de Máquina , Espectrografia do Som , Vocalização Animal
14.
Commun Biol ; 5(1): 347, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35411020

RESUMO

Large diversifications of species are known to occur unevenly across space and evolutionary lineages, but the relative importance of their driving mechanisms, such as climate, ecological opportunity and key evolutionary innovations (KEI), remains poorly understood. Here, we explore the remarkable diversification of rhacophorid frogs, which represent six percent of global amphibian diversity, utilize four distinct reproductive modes, and span a climatically variable area across mainland Asia, associated continental islands, and Africa. Using a complete species-level phylogeny, we find near-constant diversification rates but a highly uneven distribution of species richness. Montane regions on islands and some mainland regions have higher phylogenetic diversity and unique assemblages of taxa; we identify these as cool-wet refugia. Starting from a centre of origin, rhacophorids reached these distant refugia by adapting to new climatic conditions ('niche evolution'-dominant), especially following the origin of KEIs such as terrestrial reproduction (in the Late Eocene) or by dispersal during periods of favourable climate ('niche conservatism'-dominant).


Assuntos
Anuros , Reprodução , Animais , Anuros/genética , Ilhas , Filogenia , Filogeografia
15.
Environ Pollut ; 304: 119219, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35378202

RESUMO

Whalers Bay, in Deception Island, has one of the most anthropogenically impacted areas in Maritime Antarctica. However, considering the volcanic nature (high concentrations of heavy metals) of Deception Island's soils, this putative anthropogenic impact should be carefully investigated. In this context, the objective of this study was to compare resistome profiles of impacted and non-impacted areas in Deception Island (Whalers Bay, Crater Lake, and Fumarole Bay) and Livingston Island (Hannah Point) in order to investigate the microbiome tolerance/resistance mechanisms selected as a function of environmental drivers. Metagenomics was used to search for genes conferring resistance/tolerance to antibiotics, biocides, and heavy metals. Whalers Bay has a greater diversity of antibiotic, biocide, and heavy metal resistance classes found in its microbiomes. However, Hannah Point, at Livingston Island, has a greater abundance of antibiotic and biocide resistance/tolerance genes. The microbiome of Deception Island's non-impacted areas (Crater Lake and Fumarole Bay) showed resistance/tolerance genes almost entirely to heavy metals. Pb was found in higher concentrations in Whalers Bay soil in comparison to the other areas, indicating human contamination. The non-metric multidimensional scaling (NMDS) analysis revealed that Pb concentrations influenced resistome profiles in Whalers Bay soil. Despite the effect of Pb on the microbial communities of Whalers Bay, most heavy metal concentrations did not have a significant impact on resistome genes, suggesting that the volcanic soil heavy metal concentration of Deception Island has little biological influence.


Assuntos
Desinfetantes , Metais Pesados , Regiões Antárticas , Antibacterianos/análise , Desinfetantes/análise , Monitoramento Ambiental , Humanos , Ilhas , Chumbo/análise , Metais Pesados/análise , Metais Pesados/toxicidade , Solo
16.
Zootaxa ; 5093(2): 241-246, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35390808

RESUMO

A cross-sectional survey was carried out to determine sand fly fauna of the Andaman and Nicobar Islands that are known for tourist attraction from different countries, due to their scenic beauty. The study area includes 40 localities, stretching from south and middle to north Andaman Islands. Sand fly collections were made from day time resting shelters such as human dwellings, cattle-shed, and bushes in fringe of villages. A total of 1055 sand flies, comprising of six species were collected. Se. (Neo.) barraudi was found to be the predominant species, comprising of 57.7% of the total. Other species found to occur were Se. (Par.) babu (27. 4%), Se. (bailyi) 8. 1%, Se. (Neo.) gemmea (4. 9%), Se. (Neo.) quatei (2. 1%) and Phlebotomus (Ana.) stantoni (0.3%). Se. (Neo.) gemmea is reported to be a vector transmitting visceral leishmaniasis and dermal leishmaniasis in southern Thailand. Se. (Neo.) gemmea and Se (Neo.) quatei are new country records adding to the existing list of sand fly fauna of India. This is the first report on sand flies from Andaman and Nicobar Islands.


Assuntos
Phlebotomus , Psychodidae , Animais , Bovinos , Estudos Transversais , Insetos Vetores , Ilhas
17.
Zootaxa ; 5087(2): 357-371, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35390913

RESUMO

Corallana mishrai sp. nov. collected from dead mangrove roots at Kodiyaghat, South Andaman, Andaman Islands, India is described and illustrated in detail. Corallana mishrai sp. nov. the first definitive record of the genus from India, is characterized by: frontal lamina with short straight (or very weakly convex) lateral margins and the anterior margin forming a strong acute median point; pleotelson length 0.76 greatest width, posterior margin with 5 robust setae; uropodal exopod 7 times longer than greatest width, extending beyond endopod by one fourth of its length; endopod lateral margin slightly convex with 4 RS and PMS, apex forms a slightly obtuse angle with long simple setae, mesial margin weakly convex with 2 RS and PMS; mandible bidentate; transverse row of 6 tubercles present on pereonite 1 and pleonites 2, 3 and 4 lacking lateral tubercles. The status of the genus and its species are reviewed, and two species are transferred to new combinations: Argathona kulai (Bruce, 1982) comb. nov. and Tachaea bidentata (Jones et al. 1983) comb. nov.


Assuntos
Besouros , Isópodes , Animais , Oceano Índico , Ilhas
18.
Mol Phylogenet Evol ; 171: 107455, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35358692

RESUMO

The genus, Ochrosia, is widely distributed from the West Indian Ocean throughout tropical Asia to the Middle Southern Pacific region. Ochrosia comprises many island-endemic species, suggesting that long-distance dispersal and isolation after migration are key factors for clarifying the diversification process. However, the phylogeny and biogeography of endemic Ochrosia species have not been evaluated well due to the difficulty of adequate sampling from the entire distribution range of the genus. In this study, we focused on two Ochrosia species endemic to the Bonin (Ogasawara) Islands in the northwest Pacific. The Bonin Islands are of volcanic origins and consist of two islands groups, the Ogasawara and Volcano Islands groups, approximately 300 km apart. Ochrosia nakaiana is endemic to the Ogasawara Islands group, whereas O. hexandra is endemic to the Volcano Islands group. To elucidate the phylogenetic positions of these two endemic Ochrosia species, we conducted molecular phylogenetic studies with dating and biogeographic analyses including other Ochrosia species. The phylogenetic trees showed that the two endemic species had distinct origins; O. nakaiana was closely related to O. oppositifolia and O. iwasakiana, whereas O. hexandra was related to O. mariannensis. Based on the chloroplast DNA phylogeny, the genus, Ochrosia, divided into two major lineages 36.6 million years ago. Further, the two endemic species of the Bonin Islands were independently derived approximately 1-2 million years ago. Ochrosia nakaiana originated from the Southeast Asia, New Caledonia, or other Pacific Islands, while O. hexandra derived from O. mariannensis in Micronesia. We demonstrated different origins of the two endemic Ochrosia species on the Bonin Islands. This study provided an excellent example of the complex origins and speciation of flora in the oceanic islands.


Assuntos
Apocynaceae , Ochrosia , Apocynaceae/genética , DNA de Cloroplastos/genética , Ilhas , Filogenia
19.
Fungal Biol ; 126(4): 267-276, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35314058

RESUMO

Phytophthora palmivora is the causal agent of cocoa black pod disease, one of the primary diseases of cocoa in Indonesia. A better understanding of P. palmivora population genetics is needed to aid the development of relevant disease management strategies. This study is the first population genetic study of P. palmivora in Indonesia using microsatellite markers based on the alleles genotyping method. The microsatellite markers were used to determine the genotype of 44 P. palmivora isolates from Sulawesi (24) and Java (20) islands. The total number of observed multilocus genotypes (MLG) from both populations was 34. The genotypic diversity of P. palmivora from Sulawesi (2.90; 16.0; 0.938) and Java (2.76; 14.3; 0.930) islands was high as seen from Shannon's diversity index (H), Stoddart and Taylor's Index (G), and Simpson's Index (λ) respectively. Evenness and Nei's unbiased gene diversity exhibited similarly high levels from both populations. The linkage disequilibrium test indicated that sexual recombination occurred in the Java population (P = 0.312). Analysis of molecular variance (AMOVA) and Bayesian clustering revealed five genetic clusters, and isolates from both islands were evenly distributed across the five gene clusters. All genetic diversity was from within individuals. P. palmivora from Sulawesi and Java showed a high genotypic diversity but a lack of genetic differentiation among populations (Fst = 0.006). Both populations formed one highly diverse group. Minimum spanning network analysis showed no particular grouping of MLGs, and shared MLGs from both populations indicated long-distance migration of P. palmivora facilitated by human activities.


Assuntos
Phytophthora , Teorema de Bayes , Variação Genética , Genética Populacional , Genótipo , Humanos , Indonésia , Ilhas , Repetições de Microssatélites , Phytophthora/genética , Doenças das Plantas
20.
PLoS One ; 17(3): e0265224, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35353828

RESUMO

Knowledge of biodiversity in the past, and the timing, nature, and drivers of human-induced ecological change, is important for gaining deep time perspectives and for modern conservation efforts. The Marquesas Islands (Polynesia) are one of the world's most remote archipelagos and illustrate the vulnerability of indigenous bioscapes to anthropogenic activities. Characterised by high levels of endemism across many biotic groups, the full spectrum of the group's flora and fauna is nonetheless incompletely known. Several centuries of Polynesian settlement reshaped biotic communities in ways that are not yet fully understood, and historically-introduced mammalian herbivores have devastated the indigenous lowland flora. We report here on archaeological recovery of a diverse assemblage of plant and arthropod subfossils from a waterlogged deposit on the largest Marquesan island: Nuku Hiva. These materials offer new perspectives on the composition of lowland plant and arthropod communities pene-contemporaneous with human arrival. Bayesian analysis of multiple 14C results from short-lived materials date the assemblages to the mid-12th century AD (1129-1212 cal. AD, 95.4% HPD). Evidence for human activities in the catchment coincident with deposit formation includes Polynesian associated arthropods, microcharcoal, and an adzed timber. Plant macrofossils (seeds, fruits, vegetative structures) and microfossils (pollen, phytoliths) reveal coastal and lowland wet-moist forest communities unlike those observed today. Several apparently extinct taxa are identified, along with extant taxa currently constrained to high altitude and/or interior areas. A diverse inventory of subfossil arthropods-the first pre-18th century records for the islands-includes more than 100 distinct taxa, with several new archipelago records and one previously unreported for eastern Polynesia. The assemblages provide new insights into lowland Marquesan forest communities coincident with human arrival, and portend the considerable anthropogenic transformations that followed. These records also have implications for human colonisation of the Marquesas Islands and East Polynesia at large.


Assuntos
Artrópodes , Animais , Arqueologia , Teorema de Bayes , Humanos , Ilhas , Mamíferos , Plantas , Polinésia
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